1 // SPDX-License-Identifier: GPL-2.0+
24 #include <asm/text-patching.h>
53 	len = insn_length(*p->addr >> 8);  in copy_instruction()
54 	memcpy(&insn, p->addr, len);  in copy_instruction()
55 	p->opcode = insn[0];  in copy_instruction()
58 		 * For pc-relative instructions in RIL-b or RIL-c format patch  in copy_instruction()
65 		addr = (u64)(unsigned long)p->addr;  in copy_instruction()
66 		new_addr = (u64)(unsigned long)p->ainsn.insn;  in copy_instruction()
67 		new_disp = ((addr + (disp * 2)) - new_addr) / 2;  in copy_instruction()
70 	s390_kernel_write(p->ainsn.insn, &insn, len);  in copy_instruction()
88 	addr = paddr - offset;  in can_probe()
113 			insn = kp->opcode;  in can_probe()
122 	if (!can_probe((unsigned long)p->addr))  in arch_prepare_kprobe()
123 		return -EINVAL;  in arch_prepare_kprobe()
125 	if (probe_is_prohibited_opcode(p->addr))  in arch_prepare_kprobe()
126 		return -EINVAL;  in arch_prepare_kprobe()
127 	p->ainsn.insn = get_insn_slot();  in arch_prepare_kprobe()
128 	if (!p->ainsn.insn)  in arch_prepare_kprobe()
129 		return -ENOMEM;  in arch_prepare_kprobe()
143 	struct kprobe *p = args->p;  in swap_instruction()
146 	opc = args->arm_kprobe ? BREAKPOINT_INSTRUCTION : p->opcode;  in swap_instruction()
147 	s390_kernel_write(p->addr, &opc, sizeof(opc));  in swap_instruction()
180 	if (!p->ainsn.insn)  in arch_remove_kprobe()
182 	free_insn_slot(p->ainsn.insn, 0);  in arch_remove_kprobe()
183 	p->ainsn.insn = NULL;  in arch_remove_kprobe()
200 	/* Set up the PER control registers %cr9-%cr11 */  in enable_singlestep()
206 	__local_ctl_store(9, 11, kcb->kprobe_saved_ctl);  in enable_singlestep()
207 	kcb->kprobe_saved_imask = regs->psw.mask &  in enable_singlestep()
212 	regs->psw.mask |= PSW_MASK_PER;  in enable_singlestep()
213 	regs->psw.mask &= ~(PSW_MASK_IO | PSW_MASK_EXT);  in enable_singlestep()
214 	regs->psw.addr = ip;  in enable_singlestep()
223 	__local_ctl_load(9, 11, kcb->kprobe_saved_ctl);  in disable_singlestep()
224 	regs->psw.mask &= ~PSW_MASK_PER;  in disable_singlestep()
225 	regs->psw.mask |= kcb->kprobe_saved_imask;  in disable_singlestep()
226 	regs->psw.addr = ip;  in disable_singlestep()
232  * previous kprobe is stored in kcb->prev_kprobe. A stack of up to
237 	kcb->prev_kprobe.kp = __this_cpu_read(current_kprobe);  in push_kprobe()
238 	kcb->prev_kprobe.status = kcb->kprobe_status;  in push_kprobe()
245  * current state is KPROBE_REENTER prev_kprobe.kp will be non-NULL,
250 	__this_cpu_write(current_kprobe, kcb->prev_kprobe.kp);  in pop_kprobe()
251 	kcb->kprobe_status = kcb->prev_kprobe.status;  in pop_kprobe()
252 	kcb->prev_kprobe.kp = NULL;  in pop_kprobe()
258 	switch (kcb->kprobe_status) {  in kprobe_reenter_check()
285 	 * processing. That includes the calls to the pre/post handlers  in kprobe_handler()
290 	p = get_kprobe((void *)(regs->psw.addr - 2));  in kprobe_handler()
296 			 * active. This can happen in the pre and post  in kprobe_handler()
305 			kcb->kprobe_status = KPROBE_REENTER;  in kprobe_handler()
308 			 * If we have no pre-handler or it returned 0, we  in kprobe_handler()
310 			 * pre-handler and it returned non-zero, it prepped  in kprobe_handler()
315 			kcb->kprobe_status = KPROBE_HIT_ACTIVE;  in kprobe_handler()
316 			if (p->pre_handler && p->pre_handler(p, regs)) {  in kprobe_handler()
321 			kcb->kprobe_status = KPROBE_HIT_SS;  in kprobe_handler()
323 		enable_singlestep(kcb, regs, (unsigned long) p->ainsn.insn);  in kprobe_handler()
337  * Called after single-stepping.  p->addr is the address of the
340  * temporarily put back the original opcode to single-step, we
341  * single-stepped a copy of the instruction.  The address of this
342  * copy is p->ainsn.insn.
347 	unsigned long ip = regs->psw.addr;  in resume_execution()
348 	int fixup = probe_get_fixup_type(p->ainsn.insn);  in resume_execution()
351 		ip += (unsigned long) p->addr - (unsigned long) p->ainsn.insn;  in resume_execution()
354 		int ilen = insn_length(p->ainsn.insn[0] >> 8);  in resume_execution()
355 		if (ip - (unsigned long) p->ainsn.insn == ilen)  in resume_execution()
356 			ip = (unsigned long) p->addr + ilen;  in resume_execution()
360 		int reg = (p->ainsn.insn[0] & 0xf0) >> 4;  in resume_execution()
361 		regs->gprs[reg] += (unsigned long) p->addr -  in resume_execution()
362 				   (unsigned long) p->ainsn.insn;  in resume_execution()
378 	if (kcb->kprobe_status != KPROBE_REENTER && p->post_handler) {  in post_kprobe_handler()
379 		kcb->kprobe_status = KPROBE_HIT_SSDONE;  in post_kprobe_handler()
380 		p->post_handler(p, regs, 0);  in post_kprobe_handler()
387 	 * will have PER set, in which case, continue the remaining processing  in post_kprobe_handler()
390 	if (regs->psw.mask & PSW_MASK_PER)  in post_kprobe_handler()
402 	switch(kcb->kprobe_status) {  in kprobe_trap_handler()
412 		disable_singlestep(kcb, regs, (unsigned long) p->addr);  in kprobe_trap_handler()
419 		 * In case the user-specified fault handler returned  in kprobe_trap_handler()
440 	if (regs->psw.mask & (PSW_MASK_IO | PSW_MASK_EXT))  in kprobe_fault_handler()
443 	if (regs->psw.mask & (PSW_MASK_IO | PSW_MASK_EXT))  in kprobe_fault_handler()
444 		local_irq_restore(regs->psw.mask & ~PSW_MASK_PER);  in kprobe_fault_handler()
456 	struct pt_regs *regs = args->regs;  in kprobe_exceptions_notify()
459 	if (regs->psw.mask & (PSW_MASK_IO | PSW_MASK_EXT))  in kprobe_exceptions_notify()
473 		    kprobe_trap_handler(regs, args->trapnr))  in kprobe_exceptions_notify()
480 	if (regs->psw.mask & (PSW_MASK_IO | PSW_MASK_EXT))  in kprobe_exceptions_notify()
481 		local_irq_restore(regs->psw.mask & ~PSW_MASK_PER);  in kprobe_exceptions_notify()